(CNN) -- A schoolgirl in Saudi Arabia was sentenced to 90 lashes and two months in prison for assaulting her headmistress after a confrontation over a cell phone, sparking an outcry from a government-sponsored rights group.

Saudi Arabia's National Society for Human Rights said it is surprised by the verdict and called for the punishment be reconsidered, according to statement by the group.

The verdict was handed down by a court in the eastern province city of Jubail as a punishment for the 13-year-old who allegedly assaulted her headmistress.

Saudi daily newspaper, Al-Watan, which first reported the sentence, said the girl struck the headmistress on the head with a glass after a confrontation over the confiscation of the girl's camera-equipped cell phone.

Dr. Saleh Al-Khaslan, a spokesman for the rights group, said the penalty was too severe.

"The court should have looked for an alternative sentence," he said, adding that the rights group is calling on an appeals court in Jubail to hear the case again.

Al-Watan did not provide the name of the school, its headmistress or the girl. Efforts to reach the Saudi Ministry of Justice were unsuccessful.

Saudi Arabia follows a strict interpretation of Islam called Wahhabism, and lashings are a common form of punishment.

In October 2009, a court sentenced a man to five years in prison and 1,000 lashes after he bragged about his sex life on television.

In March of the same year, a Saudi court sentenced a 75-year-old Syrian woman to 40 lashes, four months imprisonment and deportation from the kingdom for having two unrelated men in her house.

In 2007, a 19-year-old gang-rape victim in the Saudi city of Qatif was sentenced to 200 lashes and six months in prison for meeting with an unrelated male. The seven attackers, who abducted the man and woman, got sentences ranging from 10 months to five years in prison. The case sparked international outrage, prompting Saudi's King Abdullah to pardon the girl and the unrelated male.